The use of precast concrete components such as slabs, columns etc in the construction industry is well known. This avoids the need for casting concrete components in situ and renders unnecessary the extra formwork and labour needed to pour, form and hold wet concrete in place until it sets. The components can instead be precast offsite, or at least away from the main construction area, and when needed the components are transported by truck and/or lifted into position by crane and incorporated into the existing structure.
Precasting is typically performed in horizontal casting beds with the extremities of the required components defined by formwork typically in the form of L-shaped extrusions. As will be appreciated, the maximum height of the component being formed will be determined by the height of the L-shaped extrusion. Thus, it may be necessary to have lengths of formwork of varying heights to suit a range of casting jobs. This is particularly necessary if components are cast progressively on top of each other.
Concrete can be brittle and easily chipped or broken where it is thinnest in a component. Typically this occurs on the comers and edges of the component during removal from the mould, transportation and placement. Such damage, which may lead to weakness and which looks unattractive where the components are to remain exposed in a structure, can be avoided by providing the component with chamfered edges. An existing method used to create the chamfer involves placing a plastic triangular sectioned component at the bottom comer of the mould created by the L-shaped sections. However, it will be appreciated that this only allows for the edge at the bottom of the mould to be chamfered.
It is therefore an object of the invention to provide a system to facilitate the production of precast concrete elements for use in the construction industry; and/or to overcome or address at least one of the disadvantages of the prior art; and/or at the least to provide the public with a useful choice.